78 www. bus- ex. com July 09 Emirate of Abu Dhabi, is even bigger at 700,000 tonnes annual capacity and will be the world's largest single- site aluminium smelter. Each of these projects represents an investment of around $ 5 billion, and that's just for the first phase: a second phase is planned at both Qatalum and Taweelah, doubling the capacity. The first phase at Qatalum comprises two buildings, or potrooms, more than a kilometre long, housing the group of cells in which aluminium is produced by electrolytic reduction. The parallel potroom buildings each house two rows of 176 electrolytic cells, known as potlines, totaling 704 cells in the first phase of the plant. DMD has been contracted to fabricate the 704 busbar assemblies that deliver power to the cells. These are not small assemblies, explains Connor. " Each assembly is around 10 metres long, and they probably stand about 3.5 metres high." They are manufactured in their entirety at the Jebel Ali workshop from sections of aluminium bolted to the carbon cathode and comprising variable conductivity elements. " For this contract we purchased a computerised guillotine from Europe for cutting the aluminium sheets so that we could fabricate what they call the ' flexibles' for the busbars." A key part of the assembly is the transition block, welded to the flexible aluminium element that joins the busbar to the carbon cathode rods that pass the current to the alumina powder in the pot. " Traditionally, these transition blocks are only provided by specialist suppliers in Europe and North America. We are trying to pursue niche markets and compete with specialist suppliers," says Connor. By developing and qualifying its own innovative methodology for welding copper to the steel and aluminium transition block, DMD has been able to take control of the production schedule and quality management for this important item, saving something like four- fifths of the cost of sourcing the transition blocks overseas. " There's a huge advantage in " We employ mainly fabricators and welders, but even if we can find experienced people, we have to give them up to four weeks of comprehensive training in- house"
Dutco McConnell Dowell activity; we're looking for 150 good MIG welders- then we will upgrade their existing skills." Building on its excellent track record, producing world-class solutions to specialised problems and establishing itself in niche technologies, DMD is extremely well positioned to grow as the organisations it works with increase their investment in line with the Gulf States' objectives, which are to diversify as their oil revenues decrease. Its pipeline experience continues to be in demand in the oilfields of the region, as does its electrical and mechanical capability. In a recent contract with Emirates National Oilfields Company ( ENOC) in Dubai, it installed 1,000 tonnes of steel, fabricated and erected process piping, and installed mechanical equipment at ENOC's Naphtha Hydrotreater Reformer plant. It carried out testing, pre- commissioning and commissioning work as well, in all clocking up more than three million man- hours without any lost- time accidents. - Editorial research by Jon Bradley July 09 www. bus- ex. com 79 being able to control that part of the work. We are making all the components; we are not relying on any suppliers other than of raw materials to fabricate these busbars. And Norsk Hydro has told us that the quality and workmanship in the end product is as good as or better than anything they have seen anywhere in the world," Connor adds with satisfaction. As a result of this innovation, the saving to the client is significant in time as well as money. The transition blocks can be manufactured in days, compared to a lead time of months from North America. As there is virtually no indigenous workforce in the UAE, all of DMD's 1,600 employees from the managing director downwards are expatriates. To keep up with his ongoing commitments, Connor has just recruited a further 350 operatives from India. " We employ mainly fabricators and welders, but even if we can find experienced people, we have to give them up to four weeks of comprehensive training in- house. Aluminium welding is a highly specialised